If you're going to spread a religion, I'd rather you did it peacefully, but I still don't really like the idea of going to people who don't have the resources or knowledge to go against what you say and convincing them that what you believe is the absolute truth.

I disagree, I have my own reasons to be hopeful. But that's it, they're mine. I'm not going to go up to other people and tell them that my reason to be hopeful isn't an opinion and that it's absolute truth.
And if someone needs to be given hope, it's my humble opinion that the hope for a better tomorrow is superior to the hope for eternal life, if you can't support the latter with something other than personal conviction and faith. Not to say conviction and faith are bad things, but they shouldn't be used to convince others.

Hope for a better tomorrow was also what missionaries brought, along with the best science that there was at the time.

Missionaries did not 'take advantage' as much as you think. they went to places and set-up things like orphanages, clinics etc etc. They set-up churches and held sermons and never forced anyone to come.

People converted because they believed in what the missionaries were doing to aid those around them.

Also being a missionary was extremely dangerous, many of them were simply killed for being different than the people they were approaching and attempting to help.